Análise da performance de um reator de eletrofloculação em batelada no tratamento de efluente à base de tinta para estruturas metálicas

Abstract

In the metal-mechanic and civil construction industries, volumes of effluent based on paints, applied in metallic finishes, are significantly generated. The improper disposal or without adequate treatment of this effluent suggests the study of techniques that may require a compact treatment unit and a satisfactory cost-benefit ratio. There are few studies on the application of electroflocculation (EF) in the removal of ink dissolved in water. As EF is considered a promising technique, this proposal aims to develop a compact system composed of a cylindrical electrolytic reactor, alternating source, polarity inverter, rectangular electrodes, and sensors. The objective of this work is to investigate the best-operating conditions of the electroflocculation system, in batch, in the treatment of a synthetic effluent produced from the mixture of paint, distilled water, and salt. In the experiments, a concentration of 100 mg.L-1, an operating volume of 3.5 L, and a residence time of 30 minutes are used. In the search for the best-operating conditions, the influence of variables of interest such as polarity inversion time and distance between electrodes on the percentage response of ink removal, turbidity and COD, pH and temperature variation, conductivity, electrode consumption, and energy cost. During the experiments, temperature, current intensity, and voltage are monitored to inform possible existing variations. This dataset provides information to estimate energy consumption and possible operational viability. Construction, assembly of the operating system, and obtaining of experimental results provide an understanding of satisfactory conditions regarding the percentage of paint removal in compliance with the standards established by current environmental legislation.